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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
341

Effect of Pressure and Temperature on Lattice Parameters of Nepheline

Freeman, Edward Bicknell 09 1900 (has links)
An experimental investigation was made involving the synthesis of nepheline (NaAlSiO4) under varying conditions of temperature and water pressure 2022-2130 for each synthesized charge was obtained using x-ray diffraction methods. It was found that the results of the individual runs provided an erratic lattice parameter variation with temperature in the range 500 to 800 degrees Celsius. However, a least squares curve indicates that no change in lattice parameters in the low-nepheline polymorph occurs with temperature of formation, for 95 percent probability. / Thesis / Master of Science (MS)
342

Improved Algorithm for Measurement of Blood Pressure based on a Laser Doppler Flowmetry Signal

Mårtensson, Sofie January 2016 (has links)
People with diabetes suffer from a high risk of developing foot related diseases. It is therefore important to perform a blood pressure measurement on the toe to be able to diagnose and treat in time. Using laser Doppler flowmetry has been proven to be a useful technique for this purpose during a standard blood pressure measurement procedure using a cuff. The laser Doppler probe detects once the blood flow returns which can then be related to the pressure value. However, the algorithm currently used by the company for detection of return of blood flow is in need of improvements. This thesis aims to develop an improved algorithm, which is more robust against artifacts. Furthermore, a warning system for uncertainties in the detection will be developed and integrated with the new algorithm. To create the algorithm an investigation of the signals’ appearances was performed to obtain an understanding of what artifacts and characteristics the algorithm should be able to handle. First three different basic approaches were implemented and tested, namely model curve, threshold and pulsations. These algorithms were then combined into two different more complex algorithms. One of them consisted of the model curve and the pulsation algorithm, the second combined algorithm consisted of the threshold algorithm and the pulsation algorithm. From the result it was found that the second combined algorithm performed best. It had a high accuracy and a well-functioning warning system. However, the algorithm had problems to correctly detect the return of flow when it is characterised by a slow increase of the perfusion. The biggest contribution by this thesis is the newly developed warning system. A false detection can lead to a false diagnose to be given if the operator is not attentive. The warning system is therefore an important feature since it can prevent this from occurring.
343

The Impact of Emotional Intelligence on Auditor Judgment

Ling, Yang 01 January 2013 (has links)
Emotions are an important underlying factor that may interact with pressure and other situational variables to influence auditors’ judgments and decisions. This study seeks to identify emotional intelligence (EI) as a key factor in dealing with emotions and pressures in an audit context. In this paper, I focus on how EI may influence the relation between job pressures (i.e., time budget pressure and client incentive pressure) on the auditor’s judgment. Specifically, I investigate the moderating effect of emotional intelligence on auditor judgments when auditors experience both internal and external pressures. The results suggest that the moderating influence of EI on auditor judgments can effectively reduce auditors’ tendency to engage in dysfunctional behavior in order to improve audit quality. Furthermore, there is a positive relation between EI and professional skepticism suggesting that auditors with high EI are more skeptical and assess higher risk than auditors with low EI. Finally, moderation analysis suggests that EI is a significant mechanism which drives the joint effects of different type of pressures on auditor judgments.
344

A noninvasive and cuffless method for the measurements of blood pressure.

January 2002 (has links)
Chan Ka Wing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references. / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Objectives --- p.1 / Chapter 1.2 --- Definitions --- p.2 / Chapter 1.2.1 --- Definition of blood pressure --- p.2 / Chapter 1.2.2 --- Definition of hypertension --- p.3 / Chapter 1.3 --- Problems related to hypertension --- p.4 / Chapter 1.4 --- The importance of measuring blood pressure --- p.4 / Chapter 1.4.1 --- Self-measurement of blood pressure --- p.5 / Chapter 1.4.2 --- Ambulatory blood pressure measurement --- p.5 / Chapter 1.5 --- Review of blood pressure measurement techniques --- p.7 / Chapter 1.5.1 --- The invasive method --- p.7 / Chapter 1.5.2 --- Noninvasive methods --- p.8 / Chapter 1.6 --- Review of currently available blood pressure meters --- p.15 / Chapter 1.7 --- Prevalence of hypertension --- p.19 / Chapter 1.7.1 --- Hong Kong --- p.19 / Chapter 1.7.2 --- Worldwide --- p.20 / Chapter 1.8 --- The market for blood pressure meters --- p.21 / Chapter 1.9 --- Organization of the thesis --- p.22 / References --- p.24 / Chapter Chapter 2 --- Measurement of the ECG-PPG interval --- p.30 / Chapter 2.1 --- Introduction --- p.30 / Chapter 2.1.1 --- Pulse transit time (PTT) --- p.30 / Chapter 2.1.2 --- Electrocardiogram (ECG) --- p.36 / Chapter 2.1.2.1 --- Measurement of the ECG signal --- p.37 / Chapter 2.1.3 --- Photoplethysmography (PPG) --- p.38 / Chapter 2.1.3.1 --- Measurement of the PPG signal --- p.41 / Chapter 2.1.4 --- Measurement of blood pressure by ECG-PPG interval --- p.43 / Chapter 2.2 --- Source of errors for measurement of the ECG-PPG interval --- p.44 / Chapter 2.2.1 --- Effects of variability of ECG-PPG intervals --- p.44 / Chapter 2.2.2 --- Effects of bending the arm --- p.49 / Chapter 2.2.3 --- Effects of an external force --- p.54 / Chapter 2.3 --- Conclusion --- p.60 / References --- p.62 / Chapter Chapter 3 --- Cuffless and Noninvasive Measurement of Blood Pressure --- p.68 / Chapter 3.1 --- Introduction --- p.68 / Chapter 3.2 --- Effects of subject-dependent calibration --- p.74 / Chapter 3.3 --- Effects of different time intervals --- p.81 / Chapter 3.4 --- The impact of using different Q-P intervals --- p.96 / Chapter 3.5 --- Real-time measurement of blood pressure --- p.104 / Chapter 3.6 --- Conclusion --- p.108 / References --- p.110 / Chapter Chapter 4 --- Motion Artifact Reduction from PPG Recordings in Ambulatory Blood Pressure Measurement --- p.114 / Chapter 4.1 --- Introduction --- p.114 / Chapter 4.2 --- Previous works --- p.115 / Chapter 4.3 --- Theory --- p.116 / Chapter 4.3.1 --- The adaptive filter --- p.117 / Chapter 4.3.2 --- Variation of step-size parameters --- p.119 / Chapter 4.3.3 --- Effects of filter length --- p.120 / Chapter 4.4 --- Experiment --- p.121 / Chapter 4.5 --- Results --- p.123 / Chapter 4.6 --- Discussion --- p.131 / Chapter 4.7 --- Conclusion --- p.133 / References --- p.135 / Chapter Chapter 5 --- Measurement of Blood Pressure using the PPG signal --- p.138 / Chapter 5.1 --- Introduction --- p.138 / Chapter 5.2 --- Theory --- p.138 / Chapter 5.3 --- Experiment --- p.142 / Chapter 5.3.1 --- Multiple linear regression (MLR) --- p.142 / Chapter 5.3.2 --- Artificial neural networks (ANNs) --- p.146 / Chapter 5.3.3 --- Results --- p.149 / Chapter 5.3.4 --- Discussion --- p.152 / Chapter 5.4 --- The implementation of the Q-P interval --- p.153 / Chapter 5.4.1 --- Results --- p.154 / Chapter 5.4.2 --- Discussion --- p.156 / Chapter 5.5 --- Conclusion --- p.157 / References --- p.158 / Chapter Chapter 6 --- Conclusion and Future Studies --- p.160 / Chapter 6.1 --- Major contributions --- p.160 / Chapter 6.2 --- Future studies --- p.162 / References --- p.165 / Appendix I --- p.166
345

Correlation between clinic-measured intraocular pressure (IOP) and disease progression in primary angle closure glaucoma (PACG). / CUHK electronic theses & dissertations collection

January 2013 (has links)
Man, Xiaofei. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 138-162). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese.
346

The association between knowledge, perceptions, medication adherence and blood pressure control among Chinese hypertensive patients. / 中國高血壓患者的知識, 感知, 藥物依從性和血壓控制之間的相互關係 / CUHK electronic theses & dissertations collection / Zhongguo gao xue ya huan zhe de zhi shi, gan zhi, yao wu yi cong xing he xue ya kong zhi zhi jian de xiang hu guan xi

January 2013 (has links)
Liu, Qilin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 97-110). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese; appendixes includes Chinese.
347

Cuffless blood pressure measurement with temperature compensation.

January 2004 (has links)
Lee Chi Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 112-121). / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Objectives --- p.1 / Chapter 1.2 --- Blood Pressure --- p.2 / Chapter 1.3 --- Hypertension --- p.3 / Chapter 1.3.1 --- Definition of Hypertension --- p.3 / Chapter 1.3.2 --- Causes and Symptoms of Hypertension --- p.3 / Chapter 1.3.3 --- Complication of Hypertension --- p.4 / Chapter 1.3.4 --- Prevalence of Hypertension --- p.4 / Chapter 1.4 --- Blood Pressure Measurement --- p.5 / Chapter 1.4.1 --- History --- p.5 / Chapter 1.4.2 --- Techniques and Methods --- p.7 / Chapter 1.4.3 --- Current Devices --- p.13 / Chapter 1.5 --- Organization of the Thesis --- p.16 / Chapter Chapter 2 --- Theory --- p.18 / Chapter 2.1 --- Introduction --- p.18 / Chapter 2.2 --- Blood Rheology --- p.18 / Chapter 2.2.1 --- Blood Composition --- p.18 / Chapter 2.2.2 --- Flow Properties of Blood --- p.19 / Chapter 2.2.3 --- Blood Vessels --- p.21 / Chapter 2.3 --- Principle of the PTT-Based Blood Pressure Measurement --- p.22 / Chapter 2.3.1 --- Wave Propagation in Blood Vessels --- p.22 / Chapter 2.3.2 --- Pulse Transit Time (PTT) --- p.27 / Chapter 2.3.3 --- Blood Pressure Measurement Based on PTT --- p.31 / Chapter 2.4 --- Effects of Temperature on Blood Pressure --- p.34 / Chapter 2.4.1 --- Human Body Temperature Regulation --- p.34 / Chapter 2.4.2 --- Physiological Responses to Decreased Temperature --- p.36 / Chapter 2.4.3 --- Effects of Temperature on Blood Pressure --- p.38 / Chapter 2.5 --- Possible Effects of Temperature on PTT-Based Blood Pressure Measurement --- p.47 / Chapter 2.5.1 --- Windkessel Model --- p.47 / Chapter 2.5.2 --- Phase Velocity --- p.49 / Chapter 2.5.3 --- Effects of temperature on PTT --- p.52 / Chapter 2.5.4 --- Possible Effects of temperature on PTT-based Blood Pressure Measurement --- p.53 / Chapter 2.6 --- Conclusion --- p.54 / Chapter Chapter 3 --- Algorithms in Calculating Pulse Transit Time: Wavelet-Based and Derivative-Based --- p.55 / Chapter 3.1 --- Introduction --- p.55 / Chapter 3.1.1 --- Wavelet Transform (WT) --- p.56 / Chapter 3.1.2 --- Wavelet Transform Modulus Maxima (WTMM) --- p.58 / Chapter 3.2 --- Experiment --- p.60 / Chapter 3.2.1 --- Subjects --- p.60 / Chapter 3.2.2 --- Equipment and Sensors --- p.61 / Chapter 3.2.3 --- Protocol --- p.61 / Chapter 3.3 --- Methods --- p.62 / Chapter 3.3.1 --- Wavelet-Based Algorithm of PTT Calculation --- p.62 / Chapter 3.3.2 --- Derivative-Based Algorithm of PTT Calculation --- p.65 / Chapter 3.3.3 --- PTT-Based Blood Pressure Estimation --- p.67 / Chapter 3.4 --- Results --- p.68 / Chapter 3.5 --- Discussion --- p.70 / Chapter 3.6 --- Conclusion --- p.72 / Chapter Chapter 4 --- Effects of Ambient Temperature on PTT-Based Blood Pressure Estimation --- p.74 / Chapter 4.1 --- Introduction --- p.74 / Chapter 4.2 --- Experiment --- p.74 / Chapter 4.2.1 --- Subjects --- p.74 / Chapter 4.2.2 --- Equipment --- p.75 / Chapter 4.2.3 --- Protocol --- p.76 / Chapter 4.3 --- Methods --- p.77 / Chapter 4.3.1 --- Features of Photoplethysmographic Signals --- p.78 / Chapter 4.3.2 --- Calculation of Pulse Transit Time (PTT) --- p.78 / Chapter 4.4 --- Results --- p.79 / Chapter 4.4.1 --- "Effects of Ambient Temperature on Blood Pressure, Heart Rate and Finger Skin Temperature" --- p.79 / Chapter 4.4.2 --- Effects of Ambient Temperature on the Features of Photoplethysmographic Signals --- p.82 / Chapter 4.4.3 --- Effects of Ambient Temperature on Pulse Transit Time --- p.84 / Chapter 4.4.4 --- PTT-Based Blood Pressure Estimation --- p.85 / Chapter 4.4.6 --- Evaluation of the Modified Equations of the PTT-Based Blood Pressure Measurement Approach --- p.89 / Chapter 4.5 --- Discussion --- p.94 / Chapter 4.6 --- Conclusion --- p.98 / Chapter Chapter 5 --- Effects of Local Temperature on PTT-Based Blood Pressure Estimation --- p.99 / Chapter 5.1 --- Introduction --- p.99 / Chapter 5.2 --- Methods --- p.99 / Chapter 5.3 --- Results --- p.100 / Chapter 5.3.1 --- "Effects of Local Temperature on Blood Pressure, Heart Rate and Finger Skin Temperature" --- p.100 / Chapter 5.3.2 --- Effects of Local Temperature on Pulse Transit Time --- p.102 / Chapter 5.3.3 --- Effects of Local Temperature on the Features of Photoplethysmographic Signal --- p.103 / Chapter 5.3.4 --- Effects of Local Temperature on PTT-Based Blood Pressure Estimation --- p.104 / Chapter 5.4 --- Discussion --- p.105 / Chapter 5.5 --- Conclusion --- p.107 / Chapter Chapter 6 --- Conclusion and Future Study --- p.108 / Chapter 6.1 --- Major Contributions --- p.108 / Chapter 6.2 --- Future Study --- p.110 / References --- p.112 / Chapter Appendix A --- Motion Artifact Reduction from PPG signal Based on a Wavelet Approach --- p.122 / Chapter A.l --- Introduction --- p.122 / Chapter A.1.1 --- Motion Artifact --- p.122 / Chapter A.1.2 --- Stationary Wavelet Transform (SWT) --- p.123 / Chapter A.2 --- Experiment --- p.124 / Chapter A.2.1 --- Subjects --- p.124 / Chapter A.2.2 --- Equipment --- p.124 / Chapter A.2.3 --- Protocol --- p.125 / Chapter A.3 --- Methods --- p.126 / Chapter A.3.1 --- Algorithm --- p.126 / Chapter A.3.2 --- Data Analysis --- p.128 / Chapter A.4 --- Results --- p.129 / Chapter A.5 --- Discussion --- p.131 / Chapter A.6 --- Conclusion --- p.133 / Reference --- p.133 / Appendix B Derivation of the Moens-Korteweg Equation --- p.134 / Reference --- p.136
348

A new model for the generation of photoplethysmographic signal with its application to the analysis of beat-to-beat blood pressure variability.

January 2004 (has links)
Gu Yingying. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 155-164). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- IPFM Model --- p.1 / Chapter 1.1.1 --- Description of IPFM Model --- p.1 / Chapter 1.1.2 --- Background of IPFM Related Modeling --- p.3 / Chapter 1.2 --- Windkessel Model --- p.8 / Chapter 1.2.1 --- Background of the Windkessel Model --- p.8 / Chapter 1.2.2 --- Windkessel Related Modeling --- p.13 / Chapter 1.3 --- Photoplethysmogram (PPG) --- p.14 / Chapter 1.3.1 --- Principle of PPG --- p.14 / Chapter 1.3.2 --- Characteristics of PPG Signal --- p.16 / Chapter 1.4 --- A Study on the Beat-to-Beat BPV --- p.18 / Chapter 1.5 --- Main Purposes of the Study --- p.19 / Chapter 1.6 --- Organization of the Thesis --- p.20 / Chapter 2 --- Spectral Analysis on the IPFM Process --- p.22 / Chapter 2.1 --- Introduction --- p.22 / Chapter 2.2 --- A Theoretical Study on the Neural Firing Rate Function --- p.23 / Chapter 2.2.1 --- Mathematical Derivation of the Neural Firing Rate --- p.23 / Chapter 2.2.2 --- Spectral Analysis of the IPFM Process --- p.27 / Chapter 2.2.3 --- Reconstruction of Neural Firing Rate through LPF --- p.30 / Chapter 2.3 --- Effects of Neural Dynamics --- p.33 / Chapter 2.4 --- Discussion & Conclusion --- p.35 / Chapter 3 --- A New Model for the Generation of PPG --- p.37 / Chapter 3.1 --- Introduction --- p.37 / Chapter 3.2 --- Principles of PPG --- p.38 / Chapter 3.2.1 --- Relationship between Pressure and Flow --- p.38 / Chapter 3.2.2 --- Peripheral Pressure and Flow Curves --- p.41 / Chapter 3.2.3 --- Generation of PPG signal --- p.43 / Chapter 3.3 --- Model Description --- p.44 / Chapter 3.3.1 --- IPFM model --- p.45 / Chapter 3.3.2 --- Windkessel model --- p.46 / Chapter 3.3.3 --- New Model for the Generation of PPG --- p.49 / Chapter 3.4 --- Simulation --- p.51 / Chapter 3.4.1 --- Generation of ECG --- p.51 / Chapter 3.4.2 --- Generation of PPG --- p.57 / Chapter 3.4.3 --- Effects of the Modulation Depth on the Output --- p.65 / Chapter 3.4.4 --- Effects of Mean Autonomic Tone on HRV --- p.72 / Chapter 3.5 --- Discussion & Conclusion --- p.75 / Chapter 4 --- A Correlation Study on the Beat-to-Beat Features of Photoplethysmographic Signals --- p.80 / Chapter 4.1 --- Introduction --- p.80 / Chapter 4.2 --- Methodology --- p.81 / Chapter 4.2.1 --- Experimental Conditions --- p.81 / Chapter 4.2.2 --- Definition of the Parameters --- p.82 / Chapter 4.3 --- Data Analysis --- p.85 / Chapter 4.3.1 --- At Normal Relaxed State --- p.85 / Chapter 4.3.2 --- At Different Levels of Contacting Force --- p.87 / Chapter 4.3.3 --- At Different Levels of Local Skin Finger Temperature --- p.90 / Chapter 4.3.4 --- At Dynamic State --- p.93 / Chapter 4.3.5 --- Repeatability Study --- p.95 / Chapter 4.3.6 --- Spectral Analysis --- p.96 / Chapter 4.4 --- Discussion --- p.98 / Chapter 5 --- The Estimation of the Beat-to-Beat Blood Pressure Variability --- p.103 / Chapter 5.1 --- Introduction --- p.103 / Chapter 5.2 --- BP Estimation using FY Interval --- p.104 / Chapter 5.2.1 --- Multi-Beat BP Estimation under Different Levels of Contacting Force --- p.104 / Chapter 5.2.2 --- Beat-to-Beat BP Estimation --- p.108 / Chapter 5.2.3 --- Repeatability Study --- p.112 / Chapter 5.3 --- A Study on the Beat-to-Beat BPV --- p.113 / Chapter 5.3.1 --- Background of the Beat-to-Beat BPV --- p.113 / Chapter 5.3.2 --- Analysis of the Beat-to-Beat BPV --- p.115 / Chapter 5.4 --- Improving the PPG Model with the Time-Varying BP --- p.120 / Chapter 5.4.1 --- Modification of the Model --- p.121 / Chapter 5.4.2 --- Simulation --- p.127 / Chapter 5.4.3 --- Application of the PPG Model --- p.132 / Chapter 5.5 --- Discussion & Conclusion --- p.134 / Chapter 6 --- A Novel Biometric Approach --- p.139 / Chapter 6.1 --- Introduction --- p.139 / Chapter 6.2 --- Human Verification by PPG Signal --- p.140 / Chapter 6.2.1 --- Experiment --- p.141 / Chapter 6.2.2 --- Feature Extraction --- p.142 / Chapter 6.2.3 --- Decision-making --- p.143 / Chapter 6.2.4 --- Results --- p.146 / Chapter 6.3 --- Discussion --- p.149 / Chapter 7 --- Conclusions --- p.151 / Chapter 7.1 --- Conclusions of Major Contributions --- p.151 / Chapter 7.2 --- Work to Be Done --- p.154
349

Noninvasive and cuffless blood pressure measurement: the effects of contacting force and dynamic exercise. / CUHK electronic theses & dissertations collection

January 2004 (has links)
Teng Xiaofei. / "June 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
350

A bio-model-based cuffless technique for non-invasive and continuous measurement of arterial blood pressure. / CUHK electronic theses & dissertations collection

January 2007 (has links)
Consequently, this study aims to develop novel technologies that can measure BP non invasively and continuously without a cuff. The proposed method estimates BP using features including pulse transit time (PTT), which is defined as the time interval from R wave of electrocardiogram to onset of photoplethysmogram within the same heart cycle. / Despite the importance of controlling blood pressure (BP) to our health, BP remains inadequately managed worldwide. Due to global ageing and change of human lifestyles, the number of hypertensives is anticipated to continue rising from approximately 1 billion in 2000 to 1.56 billion by 2025. A stumbling block to BP management is high BP usually develops without obvious symptoms. As a result, many people are unaware of their condition until severe problems such as a stroke, a heart attack or kidney failure have occurred. In China, over 100 million people do not know they have developed hypertension and are living under a potential risk to their health. In addition to high BP, variations of BP are also independent indicators of morbidity and mortality of severe diseases. Yet, sudden changes in BP are difficult to be detected by state-of-the-art BP meters, which operate on principles that require an inflatable cuff to give only a snapshot of BP. / Lastly, since the technology required information from several sensors that are placed on different body parts of a person, development of body area network (BAN) has been an important research focus. The concluding chapter of this thesis presents a new concept in this area, namely the hybrid body area network (h-BAN). In particular, the use of biological channels (bio-channels) for intra-BAN communication and securing wireless intra-BAN communication is discussed. / Nevertheless, a major challenge of this approach is its requirement of a calibration procedure. One possible solution is to calibrate against a cuff-based device, but this is inconvenient particularly when calibration has to be refreshed from time to time. Therefore, a bio-model is proposed and developed for PTT along an artery where the hydrostatic component of BP varies. The model can be applied to calibrate the cuffless PTT-based approach and estimate BP by simple movements such as hand elevation. Several experiments were conducted to validate the assumptions of this model and the results were found to be promising. / The proposed PTT-based technology was evaluated on 85 subjects (aged 57+/-29 yrs., including 39 hypertensives) whilst they were at rest in a sitting posture. A total of 999 pairs of systolic BP (SBP) and diastolic BP (DBP) estimations were made with reference to conventional cuff-based devices (i.e. a mercury sphygmomanometer and an oscillometric device) over a period of 6.4 weeks. The results of the study show that reference and estimated BP differed by 0.4+/-9.3 mmHg and 0.8+/-5.8 mmHg for SBP and DBP respectively (AAMI required mean and SD to be less than 5 and 8 mmHg correspondingly). / The results of both studies show that the accuracy of the PTT-based technique is comparable to the cuff-based approaches. This technique is potentially useful to measure BP continuously. / To conclude, this work developed a non-invasive and cuffless approach for BP measurement and addressed several key issues of this approach, i.e. the analysis, calibration, and implementation of it. The work can help to realise new BP management schemes in mobile health (m-Health) and personalised healthcare systems, which are developed to cater for the needs of the increasing aging population world-wide and to prevent and control chronic diseases like hypertension. / To further the investigation, a second study which was to investigate in a clinical setting for post-operation condition, was carried out on 8 patients (aged 55+/-18 yrs.) using the averaged invasive arterial-line and cuff readings taken at intervals of 40.0+/-24.7 min. as reference. After calibrating the new approach on each individual, it can estimate SBP and DBP within 3.3+/-6.5 mmHg and 4.3+/-6.4 mmHg of the reference for the complete set of 89 estimations. / Poon, Chung Yan Carmen. / "December 2007." / Adviser: Yuon-Ting Zhang. / Source: Dissertation Abstracts International, Volume: 69-08, Section: B, page: 4888. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 91-103). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

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